This invention relates smoking articles, and in particular to rod-shaped smoking articles containing volume expanded tobacco material.
Popular smoking articles such as cigarettes comprise a substantially rod shaped structure and include a charge of smokable material such as shredded tobacco (i.e., cut filler) surrounded by a circumscribing wrapper such as paper thereby forming a tobacco rod. In certain instances, a portion of the tobacco material can be material which has been subjected to volume expansion techniques as described by Fredrickson in U.S. Pat. No. 3,524,451; and White et al in U.S. Pat. No. 4,531,529. It has been desirable to manufacture cigarettes each having a cylindrical filter element aligned in an end-to-end relationship with the tobacco rod. Typically, filter elements are manufactured from fibrous materials such as cellulose acetate and are circumscribed by paper plug wrap. The filter element is attached to the tobacco rod using a circumscribing tipping material.
It would be desirable to provide a smoking article such as a cigarette which has a unique filter element. In addition, it would be desirable to provide an efficient and effective method for providing expanded tobacco material within a tobacco rod. Also, it would be desirable to provide a smokable rod having a very light weight but firmness comparable to a conventional tobacco rod.